Interlux Protectant & Wax Sealer

Have any of you tried Interlux Protectant & Wax Sealer on a surfboard or a yak? Does it give real UV protection, or is this mostly BS in a bottle?

http://www.yachtpaint.com/usa//product_guide/boatcare/uv_protectant.asp?ComponentID=22071&SourcePageID=6716#1